diff --git a/Cargo.toml b/Cargo.toml index 236cf4b..dffe293 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -10,3 +10,6 @@ authors = ["Paul Colomiets ", "Colin Kiegel homepage = "http://github.com/tailhook/quick-error" repository = "http://github.com/tailhook/quick-error" documentation = "http://tailhook.github.io/quick-error/" + +[dev-dependencies] +backtrace = "0.2" diff --git a/examples/backtrace.rs b/examples/backtrace.rs new file mode 100644 index 0000000..8675b8a --- /dev/null +++ b/examples/backtrace.rs @@ -0,0 +1,50 @@ +#[macro_use(quick_error)] extern crate quick_error; +extern crate backtrace; + +use std::io::{self, stderr, Read, Write}; +use std::fs::File; +use std::env; +use std::num::ParseIntError; +use std::path::{Path, PathBuf}; + +use quick_error::ResultExt; +use backtrace::Backtrace; + +quick_error! { + #[derive(Debug)] + pub enum Error { + NoFileName { + description("no file name specified") + } + Io(err: io::Error, path: PathBuf, tb: Backtrace) { + display("could not read file {:?}: {}\n{:?}", path, err, tb) + context(path: &'a Path, err: io::Error) + -> (err, path.to_path_buf(), Backtrace::new()) + } + Parse(err: ParseIntError, path: PathBuf) { + display("could not parse file {:?}: {}", path, err) + context(path: &'a Path, err: ParseIntError) + -> (err, path.to_path_buf()) + } + } +} + +fn parse_file() -> Result { + let fname = try!(env::args().skip(1).next().ok_or(Error::NoFileName)); + let fname = Path::new(&fname); + let mut file = try!(File::open(fname).context(fname)); + let mut buf = String::new(); + try!(file.read_to_string(&mut buf).context(fname)); + Ok(try!(buf.parse().context(fname))) +} + +fn main() { + match parse_file() { + Ok(val) => { + println!("Read: {}", val); + } + Err(e) => { + writeln!(&mut stderr(), "Error: {}", e).ok(); + } + } +}